JPH1016480A - Dual writing instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate an anxiety of contaminating clothing and the like by easily observing a protruding state of a writing tip. SOLUTION: A site of connecting an ink containing tube to a writing tip is formed of a flexibly bendable part. A base 38a is fixed to one side face of a rear barrel 34, and a clip 38 directed toward forward of the barrel is provided. A ball part 39 having a locking part is provided ahead of the clip, and a bulged part 33 having a locking part is provided at a predetermined position on a periphery of an intermediate barrel in opposite contact with the part 39. The ball part of the clip is connected to the locking part of the bulged part only at a position where the tip protrudes from an end port of the front barrel by rotating the barrel 34 to eliminate separation of the ball part of the clip from a barrel surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved writing instrument having a plurality of ballpoint pen writing bodies.

[0002]

2. Description of the Related Art In general, there is known a double-type writing instrument equipped with a plurality of writing objects such as a mechanical pencil and a ball-point pen so that the writing tip can be selectively protruded and retracted from an axis.

A water-based ballpoint pen has a viscosity of several mPa ·
Since it has a low viscosity of S or less, it is advantageous to be able to write with a light writing pressure, and has a characteristic that writing quality is good. However, there is a drawback that a DC phenomenon in which the ink flows slowly from the pen tip, and a reverse flow phenomenon in which the air flows in from the tip of the ballpoint pen and the ink flows out, are likely to occur. A method of preventing these phenomena by using a fiber convergence material called batting is used.

On the other hand, conventionally known oil-based ball-point pens have a high viscosity of several thousands mPa · S or more of the ink used for the ball-point pens, so that the resistance to the rotation of the ball when the ink flows out of the pen tip is high. There is a drawback that writing is bad because of large size. In addition, there is a problem in that the amount of ink flowing out from the tip during writing is small, there is a dent phenomenon, the writing line is uneven, the writing density is low, and a high writing pressure is required.

As an improvement of the oil-based ballpoint pen, recently,
A ballpoint pen for water-based ink called a medium viscosity using an ink having an intermediate viscosity region between water and oil (several mPa · S to several thousand mPa · S) has been developed. This is a ballpoint pen using a relatively low-viscosity water-based ink having a characteristic of lowering the viscosity by the rotation of the tip ball and smoothly flowing out the ink, that is, a so-called shear thinning property. Further, as an improvement of the oil-based ballpoint pen, a ballpoint pen using a low-viscosity oil-based ink having excellent drying resistance can be considered.

The ballpoint pens using the medium-viscosity water-based ink and the low-viscosity oil-based ink are all low-viscosity, so that when the tip side is turned downward, a gap between the tip ball and the chip holding portion is generated. There is a phenomenon in which the ink tends to flow backward due to a direct current problem in which ink bleeds, upward writing, impact, or the like. If the ink causes backflow or direct current, there is a risk of soiling clothes and the like. In addition, when mounted on a writing instrument and inserted into a breast pocket or the like with the writing tip protruding, there is a problem in that clothes are soiled.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a writing tip having a mechanism capable of maintaining the drying resistance, allowing the seal cap to be left unattended, and preventing direct current or backflow of ink. Constitutes a medium-viscosity water-based, low-viscosity oil-based ballpoint pen, and is equipped with a plurality of large, non-deformable ballpoint pens, allowing the writing tip to appear and disappear smoothly. The protruding state of the writing tip can be easily recognized by making it impossible to insert it into the breast pocket etc. with the protruding part, so it is possible to provide a simple writing instrument with a simple structure that does not have to worry about soiling clothes etc. And

[0008]

SUMMARY OF THE INVENTION According to the present invention, a plurality of ballpoint pen writing bodies are mounted in a shaft cylinder composed of a center shaft and a front shaft detachably attached to the front end of the center shaft, and selectively mounted on each of the respective shafts. In a double-type writing instrument in which a writing tip can be alternately protruded and retracted from a tip end of a front axis, a ball-point writing body is provided on a rear axis fixed only rotatable with respect to a center axis and a spiral groove provided on the inner periphery of the rear axis. By engaging the sliding protrusion provided so as to interlock with and rotating the rear shaft, the ballpoint pen writing body can move back and forth,
In addition, the ink storage portion of the ballpoint pen writing body is substantially non-deformable and is inserted without swinging into the shaft, and the portion connecting the ink storage portion and the writing tip portion can be flexibly displaceable. It consists of.

A clip having a base fixed to one side surface of the rear shaft and disposed toward the front of the barrel, and a ball provided with a locking portion at the tip of the clip are provided. A swelling portion provided with a locking portion is provided at a predetermined position on the peripheral surface of the central shaft that is in contact with the clip, and only when the rear shaft is rotated and the writing tip projects from the tip opening of the front shaft, the ball of the clip The engaging portion of the bulging portion and the engaging portion are engaged with each other so that the ball portion of the clip does not separate from the peripheral surface of the center shaft.

The ballpoint pen writing body has a tip for holding the tip ball and an ink storage tube at the rear, and the viscosity of the tip ball is reduced by the rotation of the tip ball accompanying the writing and flows out into the ink storage tube. A water-based ballpoint pen ink or a low-viscosity oil-based ink having a shear-thinning property is filled, and the rear end of the ink is filled with a follower made of a grease-like translucent non-drying substance that moves following the consumption of the ink accompanying writing. Consisting of The ballpoint pen writing body includes a spring provided so that the tip ball always presses and contacts the inner edge of the ball holding portion at the tip of the tip, and the contact state is released during writing. Further, the ballpoint pen writing body is provided with a valve chamber in which a ball valve is loosely fitted in contact with a rear end of the chip, and a ball receiving seat for preventing backflow of ink due to a close contact of the ball valve with the rear of the valve chamber. A guide hole is provided from the receiving seat to the ink storage tube.

[0011]

FIG. 1 to FIG. 4 show a first embodiment of the present invention. In FIG. 1, two ballpoint pen writing bodies 1a and 1b are provided. The dual writing implement intended by the present invention is a ballpoint pen writing medium filled with a so-called middle viscosity aqueous or low viscosity oily ballpoint pen ink having a shear thinning property, or a normal oily ballpoint pen writing body equipped with a large volume of ink. Are used in combination as needed.

First, a ballpoint pen writing body mounted on the double-type writing instrument of the present invention will be described. Note that the ballpoint pen writing bodies 1a and 1b have the same configuration, and have different ink colors, for example. Further, the ink applied to the ballpoint pen writing material is mainly a medium-viscosity aqueous and low-viscosity oil-based ink having a so-called shear thinning property.

The tip 11 is caulked so that the tip ball 12 is rotatably held with the tip ball 12 substantially in contact with a seat having a channel into which ink can flow. Further, the spring 14 is inserted into the inner hole of the chip 11, and the rear end of the chip is appropriately caulked so that the rear end of the spring 14 cannot be pulled out. In addition, it is extremely important that the tip ball 12 is in close contact with the inner surface of the tip holding portion in order to dry the writing tip and to prevent direct current of ink. Therefore, the surface roughness of the tip holding the tip ball and the caulking In order to improve the close contact accuracy, grinding of the inner surface and secondary plastic working to increase the crimping accuracy are considered. or,
The surface treatment etc. are considered in the close contact surface with the tip ball.
Further, the tip of the spring 14 becomes a straight rod shaft portion 15, and the tip of the rod portion 15 comes into contact with the back surface of the tip ball 12 in a pressed state. In addition, the tip ball 12 is pressed by the pressing to
The first ball holding portion (formed by caulking or the like) is in close contact with the inner edge.

The joint 2 has a front shaft 3 for pressing the tip 11 at the tip and a rear shaft 5 for pressing the front end of the ink storage tube 17 at the front end, between the front shaft 3 and the rear shaft 5. Are formed of a resin molded product integrally connected by a flexible displaceable bendable portion 4. A valve chamber 7 in which a ball valve 16 is loosely fitted is provided in the joint 2 so as to face the rear end of the chip 11. When the chip 11 is downward, the guide hole 9 is opened and the ink 18 is filled with the chip 18. The ball valve 16 is configured to seal the guide hole 9 to prevent the ink from flowing backward when the ball valve 16 is in the upward direction.

By the way, the cross section of the ink container 17 is substantially D-shaped (not shown), and becomes substantially circular with two flat portions in contact with each other. 43
To be installed in the inner space of the car without waste. In the case of three ink containers, the cross section of the ink storage tube is formed in a substantially fan shape obtained by dividing a circle into 120 degrees. The ink storage tube 17 is filled with the above-mentioned medium-viscosity water-based or low-viscosity oil-based ink, and the rear end of the ink is in the form of a grease that can move following the ink surface as the ink is consumed. Is filled with a follower 19 made of a translucent non-drying material. In the follower 19, a resin-made follower rod 20 having substantially the same specific gravity as the follower is immersed.

A shaft portion 22 in front of the sliding piece 21a is press-fitted and fixed to the rear end hole of the ink storage tube 17. Further, a ventilation groove 23 for communicating the inside of the ink storage tube 17 with the outside air is provided on the peripheral surface of the shaft portion 22. The rear shaft portion 24 of the sliding piece 21a is provided with two pieces 24a and 24b, and a guide rib 25 is provided on one side of the piece 24a. 26 are formed. Thus, the ballpoint pen writing body 1a is configured.
The ballpoint pen writing body 1b is similarly configured.

The double-type writing instrument of FIG. 1 includes two types of ballpoint pen writing bodies, a center shaft 30 for accommodating the ballpoint pen writing body, a front shaft 43 fixed in front of the center shaft 30 by screw connection,
Also, a rear shaft 3 fixed to the rear of the center shaft 30 so as to be rotatable only.
Consists of four. Also, the rear shaft 34 is removed from the center shaft 30 to replace the cursive writing. In addition, the sliding pieces 21a, 21b and the ink storage tube 17 are detachable, and the ball point pen writing bodies 1a, 1b can be replaced by removing the front shaft 43 from the center shaft 30.

By the way, the bulge 33 is formed at two places on the outer periphery of the center shaft 30 slightly rearward, and a locking portion composed of a convex 33b and a concave 33a is formed on the front of the bulge 33. . As shown in FIGS. 1 and 2, a tubular portion 31 extends behind the bulging portion 33, and has a circumferential protruding portion 32 a on the peripheral surface of the tubular portion 31, further rearward, and at the rear end. Two open slit portions 32b are formed, the ballpoint pen writing bodies 1a, 1b are inserted into the center shaft 30, and the sliding pieces provided at the rear ends of the ballpoint pen writing bodies 1a, 1b in the respective slit sections 32b. Guide ribs 25 of 21a and 21b,
The sliding protrusion 26 is inserted.

As shown in FIG. 3, the rear shaft 34 is a cylindrical body having a crown 36 closed at the rear end, and a clip 38 connected to one side of a rear outer peripheral portion of the cylindrical body by a base 38a is provided forward. It has been extended. Also, the convex portion 4 is provided on the rear surface of the ball portion 39 of the clip 38.
A locking portion composed of a 0 and a concave portion 41 is formed, and the convex portion 40 of the ball portion 39 is disengaged from the concave portion 33a of the bulging portion 33 by the circumferential movement of the clip accompanying the rotation of the rear shaft 34 described later. . A circumferential groove 35 is formed on the inner periphery of the front end of the rear shaft 34, and a spiral groove 42 is formed on the inner periphery of the rear end.
Further, an annular rib 37 extending from the crown 36 is formed at the rear thereof.

As described above, the rear shaft 34 is fitted into the cylindrical portion 31 of the shaft cylinder, the projection 32a is engaged with the concave groove 35 by elastic deformation, and the rear shaft 34 is rotatable with respect to the shaft cylinder 30 and is prevented from falling off. At this time, the sliding projections 26 of the sliding pieces 21a and 21b are respectively engaged with the spiral grooves 42 by elastic deformation, and
With the rotation of the rear shaft 34 with respect to 0, the ballpoint pen writing materials 1a, 1
b alternately moves back and forth so that each writing tip is
3 can come out from the front end port. At this time, the ink storage tube 17 is not deformed as described above, but can be smoothly operated by the bendable portion 4.

FIGS. 5 and 6 show a second embodiment of the present invention. In the first embodiment, the rear shaft is rotated by approximately 180 degrees with respect to the center shaft so that the tip of each ball-point pen can be protruded and retracted from the front end of the barrel. In the example, the rear shaft 50 is approximately 36 with respect to the center shaft 30b.
It is designed to be rotated 0 degrees. In this case,
Since the rotation resistance can be reduced, the stroke of the cursive writing can be increased, and therefore, there is an advantage that the forward shape of the barrel can be smartly designed. In addition, the bulging portion 5
3 may be one place.

[0022]

When the rear shaft is rotated in one direction with respect to the center shaft, the sliding projections of the sliding pieces a slide along the spiral groove with the rotation of the rear shaft. Is moved forward and the other is retracted, so that the writing tip of the writing body on the advancing side can be projected from the tip end of the front shaft 43. Further, even if the ink storage portion of the writing pen of the ballpoint pen is not deformed, the writing tip portion flexibly shifts, so that the writing tip portion smoothly comes out of the tip opening without disturbing the operation.

When the ballpoint pen writing body 1a is in a protruding state, as shown in FIGS. 1 and 5, the ball portion of the clip and the swelling portion of the peripheral surface of the barrel are engaged with each other. Is in a state where it cannot be inserted into a breast pocket or the like.

Next, when the rear shaft 34 is rotated to the other side, the sliding piece 21a is retracted so that the writing tip of the ballpoint pen writing body 1a is immersed in the tip opening of the front shaft 43 and the sliding piece 21
b moves forward. At this time, the writing tip is brought into the portable state in which it is accommodated in the front shaft 43, and the clip for that state is at the position where the engagement with the bulging portion is released, and the clip can be easily inserted into a breast pocket or the like. .

When the rear shaft 34 is further rotated, the sliding piece 21a is rotated.
Is further retracted, the sliding piece 21b further advances, and the writing tip of the ballpoint pen writing body 1b projects from the tip end of the front shaft 43. In this state, the clip and the bulge of the peripheral surface of the shaft cylinder are engaged with each other so that the clip cannot be inserted into a breast pocket or the like.

The ballpoint pen writing body 1a is
When the ball valve 16 faces upward, the ball valve 16 is positioned on the ball receiving seat 8 of the valve chamber 7 and seals the guide hole 9.
Even if the ink is written upward and the ink on the back surface of the tip ball 12 of the chip runs out, the ink is caught by the head and does not flow backward. Therefore, when the chip 11 is turned downward, the ink can immediately flow out, and the writing is prevented from being rubbed.
(By the way, in the structure without a ball valve, the ink acts in the backward direction when writing upwards, so that air is trapped in the chip and the ink does not follow immediately when writing downwards, causing scuffing.)

In a writing state in which the chip 11 is directed downward, the ball valve 16 abuts on one of the rear ends of the chip 11 in a biased state, and the other side has a flow path through which ink can flow into the chip 11. Then, the ink 18 that has entered the valve chamber 7 from the ink storage tube 17 through the guide hole 9 is guided to the back of the tip ball 12. In this state, the tip ball 12 is brought into close contact with the inner edge of the chip holding portion by the pressing of the rod shaft portion 15, so that the direct current of the ink is prevented. In addition, the tip ball 12 slightly retreats due to the writing pressure, so that a gap is created and ink can flow out. By writing, the rotation of the tip ball 12 allows the ink to flow smoothly, and there is no dent and writing with high handwriting density is possible. Becomes On the back surface of the tip ball 12, there is a channel (a seat for the tip ball having a plurality of ink inflow grooves penetrating toward the inner hole of the chip), and the rod shaft portion 15 passes through the center hole of the channel. The ink in the chip is guided to the back of the tip ball 12 through the ink inflow groove and the gap between the center hole and the rod shaft portion 15.

[0028]

The composition and operation of the double-type writing instrument of the present invention are as described above. The dry end of the writing tip is maintained, the seal cap can be removed and the writing tip can be left, and direct current and reverse flow of ink can be prevented. Medium viscosity aqueous with a mechanism to enable
Constructs a low-viscosity oil-based ballpoint pen, with multiple large, non-deformable ballpoint pen-cursives, allowing the writing tip to smoothly appear and disappear. Since it cannot be inserted into a breast pocket, the protruding state of the writing tip can be easily recognized, preventing damage to the human body and clothing due to the sharp edge of the writing tip, and without having to worry about soiling the clothes, etc. Cursive and
Since it is simply composed of the front shaft, the center shaft, and the rear shaft, it can be provided at low cost.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing the entirety of a double-type writing instrument according to a first embodiment of the present invention, which is partially not shown in section. 2
It has a kind of ballpoint pen cursive.

FIG. 2 is an external view of a main part showing a rear part of a center shaft.

FIG. 3 is a sectional view of a rear shaft.

FIG. 4 is a longitudinal sectional view of a ballpoint pen writing body used in the present invention.

FIG. 5 is a longitudinal sectional view showing the entirety of a double-type writing instrument according to a second embodiment of the present invention, which is partially not shown in section.

FIG. 6 is a sectional view of a rear shaft used in the second embodiment.

[Explanation of symbols]

 1a Ballpoint pen writing body 1b Ballpoint pen writing body 2 Joint 3 Front shaft part 4 Bendable part 5 Rear shaft part 6 Flange part 7 Valve room 8 Ball receiving seat 9 Guide hole 10 Inner hole part 11 Chip 12 Tip ball 13 Shaft part 14 Spring 15 Rod shaft part 16 Ball valve 17 Ink storage tube 18 Ink 19 Follower 20 Follower rod 21a Sliding piece 21b Sliding piece 22 Shaft part 23 Vent groove 24 Rear shaft part 24a One part 24b One part 25 Guide rib 26 Sliding protrusion 30 Middle shaft 30a female screw 30b center shaft 31 cylindrical portion 32a protrusion 32b slit portion 33 bulge portion 33a concave portion 33b convex portion 34 rear shaft 35 concave groove 36 crown crown 37 annular rib 38 clip 38a base 39 ball portion 40 convex portion 41 concave portion 42 spiral groove 43 Front shaft 43a Male screw 50 Rear shaft 51 Spiral groove 52 Spiral groove 53 Swelling part

Claims (5)

[Claims] 1. A plurality of ballpoint pen writing bodies are mounted in a shaft cylinder composed of a center shaft and a front shaft detachably attached to the front of the center shaft, and each writing tip is selectively placed at the end of the front shaft. In a compound writing tool that can alternately appear and disappear from the end opening, a rear shaft fixed only rotatable with respect to the center shaft and a spiral groove provided on the inner periphery of the rear shaft so as to interlock with the ballpoint pen writing body. By engaging the moving projection and rotating the rear shaft, the writing pen of the ball-point pen can move back and forth, and the ink storage portion of the writing pen of the ball-point pen is substantially non-deformed and inserted into the shaft without swinging. A compound writing instrument, wherein a portion connecting the ink storage portion and the writing tip portion is formed of a flexible displaceable bendable portion. 2. A clip having a base fixed to one side surface of a rear shaft and disposed toward the front of the barrel, and a ball provided with a locking portion at a forward end of the clip. A swelling portion provided with a locking portion is provided at a predetermined position on the peripheral surface of the central shaft that is in contact with the clip, and only when the rear shaft is rotated and the writing tip projects from the tip opening of the front shaft, the ball of the clip 2. The dual writing implement according to claim 1, wherein the engaging portion of the bulging portion and the engaging portion are engaged with each other so that the ball portion of the clip does not separate from the peripheral surface of the central shaft. 3. The ballpoint pen writing body has a tip for holding the tip ball and an ink storage tube at the rear, and the viscosity of the tip ball is reduced by the rotation of the tip ball accompanying writing and flows out into the ink storage tube. Filled with water-based ballpoint pen ink or so-called low-viscosity oil-based ink with so-called shear-thinning properties, and the rear end of the ink is filled with a follower made of a grease-like translucent non-drying substance that moves following the consumption of ink accompanying writing. The double-type writing instrument according to claim 1, wherein the writing instrument is formed. 4. The ballpoint pen writing body has a spring provided such that the tip ball always presses and contacts the inner edge of the ball holding portion at the tip of the tip, and the contact state is released during writing. The dual writing implement according to claim 3, wherein 5. The ball-point pen writing body is provided with a valve chamber in which a ball valve is loosely fitted in contact with a tip end of the tip, and the ball valve is in close contact with a rear portion of the valve chamber to prevent a backflow of ink. 5. The dual writing implement according to claim 4, further comprising a guide hole extending from the ball receiving seat to the ink storage tube.